well it depends i think
cost of living in kathmandu specificly can range from rupian 2-3hazar to rupian 1 lakh or as much u can spend
here are the few expenses
kotha vada can ranges from  rupian 1000 to  rupian 7000 or can find expensive one also
momo rupian 10 dekhin rupian 100
pizza rupian  700 dekhin rupian 2000
travelling expenses by bus rupian 5 dekhin rupian 20
car rupian 500- rupian 1000
raksi rupian 5 dekhin rupian 6000

average cheap living expenses per month is rupian 3500 to  rupian 4500
average expensive living expenses per month rupian 7000 to rupian 1 lakh or as much as u can spend

so it tottally depends